modules/stdlib.c

   1 /* GNU m4 -- A simple macro processor
   2    Copyright (C) 1999, 2000, 2001, 2006, 2007, 2008, 2009 Free
   3    Software Foundation, Inc.
   4
   5    This file is part of GNU M4.
   6
   7    GNU M4 is free software: you can redistribute it and/or modify
   8    it under the terms of the GNU General Public License as published by
   9    the Free Software Foundation, either version 3 of the License, or
  10    (at your option) any later version.
  11
  12    GNU M4 is distributed in the hope that it will be useful,
  13    but WITHOUT ANY WARRANTY; without even the implied warranty of
  14    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15    GNU General Public License for more details.
  16
  17    You should have received a copy of the GNU General Public License
  18    along with this program.  If not, see <http://www.gnu.org/licenses/>.
  19 */
  20
  21 #include <config.h>
  22
  23 #include <pwd.h>
  24 #if TM_IN_SYS_TIME
  25 #  include <sys/time.h>
  26 #else
  27 #  include <time.h>
  28 #endif
  29 #include <sys/utsname.h>
  30
  31 /* Build using only the exported interfaces, unless NDEBUG is set, in
  32    which case use private symbols to speed things up as much as possible.  */
  33 #ifndef NDEBUG
  34 #  include <m4/m4module.h>
  35 #else
  36 #  include "m4private.h"
  37 #endif
  38
  39 /* Rename exported symbols for dlpreload()ing.  */
  40 #define m4_builtin_table        stdlib_LTX_m4_builtin_table
  41
  42 /*         function     macros  blind   side    minargs maxargs */
  43 #define builtin_functions                                       \
  44   BUILTIN (getcwd,      false,  false,  false,  0,      0  )    \
  45     BUILTIN (getenv,    false,  true,   false,  1,      1  )    \
  46     BUILTIN (getlogin,  false,  false,  false,  0,      0  )    \
  47     BUILTIN (getpid,    false,  false,  false,  0,      0  )    \
  48     BUILTIN (getppid,   false,  false,  false,  0,      0  )    \
  49     BUILTIN (getuid,    false,  false,  false,  0,      0  )    \
  50     BUILTIN (getpwnam,  false,  true,   false,  1,      1  )    \
  51     BUILTIN (getpwuid,  false,  true,   false,  1,      1  )    \
  52     BUILTIN (hostname,  false,  false,  false,  0,      0  )    \
  53     BUILTIN (rand,      false,  false,  false,  0,      0  )    \
  54     BUILTIN (srand,     false,  false,  false,  0,      1  )    \
  55     BUILTIN (setenv,    false,  true,   false,  2,      3  )    \
  56     BUILTIN (unsetenv,  false,  true,   false,  1,      1  )    \
  57     BUILTIN (uname,     false,  false,  false,  0,      0  )    \
  58
  59
  60 #define BUILTIN(handler, macros, blind, side, min, max) M4BUILTIN (handler);
  61   builtin_functions
  62 #undef BUILTIN
  63
  64 const m4_builtin m4_builtin_table[] =
  65 {
  66 #define BUILTIN(handler, macros, blind, side, min, max)                 \
  67   M4BUILTIN_ENTRY (handler, #handler, macros, blind, side, min, max)
  68
  69   builtin_functions
  70 #undef BUILTIN
  71
  72   { NULL, NULL, 0, 0, 0 },
  73 };
  74 \f
  75 /**
  76  * getcwd()
  77  **/
  78 M4BUILTIN_HANDLER (getcwd)
  79 {
  80   /* FIXME - Use gnulib module for arbitrary-length cwd.  */
  81   char buf[1024];
  82   char *bp;
  83
  84   bp = getcwd (buf, sizeof buf);
  85
  86   if (bp != NULL)               /* in case of error return null string */
  87     m4_shipout_string (context, obs, buf, SIZE_MAX, false);
  88 }
  89
  90 /**
  91  * getenv(NAME)
  92  **/
  93 M4BUILTIN_HANDLER (getenv)
  94 {
  95   char *env;
  96
  97   env = getenv (M4ARG (1));
  98
  99   if (env != NULL)
 100     m4_shipout_string (context, obs, env, SIZE_MAX, false);
 101 }
 102
 103 /**
 104  * setenv(NAME, VALUE, [OVERWRITE])
 105  **/
 106 M4BUILTIN_HANDLER (setenv)
 107 {
 108   int overwrite = 1;
 109
 110   if (argc >= 4)
 111     if (!m4_numeric_arg (context, m4_arg_info (argv), M4ARG (3), M4ARGLEN (3),
 112                          &overwrite))
 113       return;
 114
 115 #if HAVE_SETENV
 116   setenv (M4ARG (1), M4ARG (2), overwrite);
 117 #else
 118 #if HAVE_PUTENV
 119   if (!overwrite && getenv (M4ARG (1)) != NULL)
 120     return;
 121
 122   assert (obstack_object_size (obs) == 0);
 123   obstack_grow (obs, M4ARG (1), M4ARGLEN (1));
 124   obstack_1grow (obs, '=');
 125   obstack_grow0 (obs, M4ARG (2), M4ARGLEN (2));
 126
 127   {
 128     char *env = (char *) obstack_finish (obs);
 129     putenv (env);
 130   }
 131 #endif /* HAVE_PUTENV */
 132 #endif /* HAVE_SETENV */
 133 }
 134
 135 /**
 136  * unsetenv(NAME)
 137  **/
 138 M4BUILTIN_HANDLER (unsetenv)
 139 {
 140
 141 #if HAVE_UNSETENV
 142   unsetenv (M4ARG (1));
 143 #endif /* HAVE_UNSETENV */
 144 }
 145
 146 /**
 147  * getlogin()
 148  **/
 149 M4BUILTIN_HANDLER (getlogin)
 150 {
 151   char *login;
 152
 153   login = getlogin ();
 154
 155   if (login != NULL)
 156     m4_shipout_string (context, obs, login, SIZE_MAX, false);
 157 }
 158
 159 /**
 160  * getpid()
 161  **/
 162 M4BUILTIN_HANDLER (getpid)
 163 {
 164   m4_shipout_int (obs, getpid ());
 165 }
 166
 167 /**
 168  * getppid()
 169  **/
 170 M4BUILTIN_HANDLER (getppid)
 171 {
 172   m4_shipout_int (obs, getppid ());
 173 }
 174
 175 /**
 176  * getpwnam(NAME)
 177  **/
 178 M4BUILTIN_HANDLER (getpwnam)
 179 {
 180   struct passwd *pw;
 181
 182   pw = getpwnam (M4ARG (1));
 183
 184   if (pw != NULL)
 185     {
 186       m4_shipout_string (context, obs, pw->pw_name, SIZE_MAX, true);
 187       obstack_1grow (obs, ',');
 188       m4_shipout_string (context, obs, pw->pw_passwd, SIZE_MAX, true);
 189       obstack_1grow (obs, ',');
 190       m4_shipout_int (obs, pw->pw_uid);
 191       obstack_1grow (obs, ',');
 192       m4_shipout_int (obs, pw->pw_gid);
 193       obstack_1grow (obs, ',');
 194       m4_shipout_string (context, obs, pw->pw_gecos, SIZE_MAX, true);
 195       obstack_1grow (obs, ',');
 196       m4_shipout_string (context, obs, pw->pw_dir, SIZE_MAX, true);
 197       obstack_1grow (obs, ',');
 198       m4_shipout_string (context, obs, pw->pw_shell, SIZE_MAX, true);
 199     }
 200 }
 201
 202 /**
 203  * getpwuid(UID)
 204  **/
 205 M4BUILTIN_HANDLER (getpwuid)
 206 {
 207   struct passwd *pw;
 208   int uid;
 209
 210   if (!m4_numeric_arg (context, m4_arg_info (argv), M4ARG (1), M4ARGLEN (1),
 211                        &uid))
 212     return;
 213
 214   pw = getpwuid (uid);
 215
 216   if (pw != NULL)
 217     {
 218       m4_shipout_string (context, obs, pw->pw_name, SIZE_MAX, true);
 219       obstack_1grow (obs, ',');
 220       m4_shipout_string (context, obs, pw->pw_passwd, SIZE_MAX, true);
 221       obstack_1grow (obs, ',');
 222       m4_shipout_int (obs, pw->pw_uid);
 223       obstack_1grow (obs, ',');
 224       m4_shipout_int (obs, pw->pw_gid);
 225       obstack_1grow (obs, ',');
 226       m4_shipout_string (context, obs, pw->pw_gecos, SIZE_MAX, true);
 227       obstack_1grow (obs, ',');
 228       m4_shipout_string (context, obs, pw->pw_dir, SIZE_MAX, true);
 229       obstack_1grow (obs, ',');
 230       m4_shipout_string (context, obs, pw->pw_shell, SIZE_MAX, true);
 231     }
 232 }
 233
 234 /**
 235  * hostname()
 236  **/
 237 M4BUILTIN_HANDLER (hostname)
 238 {
 239   char buf[1024];
 240
 241   if (gethostname (buf, sizeof buf) < 0)
 242     return;
 243
 244   m4_shipout_string (context, obs, buf, SIZE_MAX, false);
 245 }
 246
 247 /**
 248  * rand()
 249  **/
 250 M4BUILTIN_HANDLER (rand)
 251 {
 252   m4_shipout_int (obs, rand ());
 253 }
 254
 255 /**
 256  * srand()
 257  **/
 258 M4BUILTIN_HANDLER (srand)
 259 {
 260   int seed;
 261
 262   if (argc == 1)
 263     seed = time (0L) * getpid ();
 264   else
 265     {
 266       if (!m4_numeric_arg (context, m4_arg_info (argv), M4ARG (1),
 267                            M4ARGLEN (1), &seed))
 268         return;
 269     }
 270
 271   srand (seed);
 272 }
 273
 274 /**
 275  * uname()
 276  **/
 277 M4BUILTIN_HANDLER (uname)
 278 {
 279   struct utsname ut;
 280
 281   if (uname (&ut) == 0)
 282     {
 283       m4_shipout_string (context, obs, ut.sysname, SIZE_MAX, true);
 284       obstack_1grow (obs, ',');
 285       m4_shipout_string (context, obs, ut.nodename, SIZE_MAX, true);
 286       obstack_1grow (obs, ',');
 287       m4_shipout_string (context, obs, ut.release, SIZE_MAX, true);
 288       obstack_1grow (obs, ',');
 289       m4_shipout_string (context, obs, ut.version, SIZE_MAX, true);
 290       obstack_1grow (obs, ',');
 291       m4_shipout_string (context, obs, ut.machine, SIZE_MAX, true);
 292     }
 293 }
 294
 295 /**
 296  * getuid()
 297  **/
 298 M4BUILTIN_HANDLER (getuid)
 299 {
 300   m4_shipout_int (obs, getuid ());
 301 }